A diesel particulate filter (DPF) may remove combustible (carbonaceous) and incombustible particulate matter (PM) from an exhaust gas stream of an engine. Combustible particulate is a complex blend of solid carbon and organic compounds, and may result from the incomplete combustion of diesel fuel in a cylinder of the engine. Incombustible particulate is generated from additives in lubrication oil or fuel for the engine, and material eroded from the engine surfaces. Under some circumstances, the combustible PM may fully combust during filter regeneration and thus exit the filter as gaseous CO2 and H2O. In general, the incombustible particulate cannot be converted to gaseous components and may be trapped in the filter as various oxides or other compounds (collectively called “ash”).
A DPF may require periodic cleaning to remove ash structures formed in channels of the DPF. A pressurized fluid may be applied to outer surfaces of the DPF to clean it. The ash structures, however, may be strong enough to resist removal by such application of pressurized fluid.
Each channel of the DPF may be probed with a solid rod to dislodge the ash structures from the channels. Such probing, however, may not remove the ash being broken apart and may, instead, pack the ash making it more difficult to remove.